1. Field of the Invention
The present invention relates to an image processing apparatus and a method for generating a combined image by combining a plurality of photographed images.
2. Description of the Related Art
Conventionally, radiographic imaging has been successfully used in various fields. Particularly in medical fields, the photographing using radiation is one of the most important methods for diagnosis. In recent years, an image sensor for collecting radiation images obtained by radiography as digitized image data has been put into practical use. Digitalization has progressed in the field of radiography. Generally, mainstream large-sized image sensors have a size of 43 centimeters (cm) by 43 cm.
If radiography is to be performed on a region (e.g., the whole spine or the full lower leg of a subject) larger than the image sensor, the entire region cannot be photographed by a single time of shooting (single shot). Accordingly, the object is photographed by taking a plurality of partial images thereof at a plurality of times of shooting (multiple shots), respectively. Indeed, a shooting method has been established, in which large image data representing a desired single image of the entire object is obtained by combining a plurality of pieces of image data, which are respectively acquired at the plurality of times of shooting. Generally, such a shooting method is called a divisional shooting method, a long-size shooting method, a stitch shooting method, or the like (hereinafter, such a shooting method is generally referred to as a stitch shooting method).
In the radiography in the medical field, misshooting or reshooting is designated with respect to a photographed image in view of a case where a patient moves when an image thereof is photographed. In some countries and regions, it is obligated to retain, at that time, a reason for misshooting or reshooting as a record.
Japanese Patent No. 3679647 discusses the above misshooting or reshooting. Hereinafter, a conventional method for designating the misshooting or reshooting is described with reference to FIGS. 9A and 9B. As illustrated in FIGS. 9A and 9B, a combined image C4 is obtained by combining three photographed images C1, C2, and C3 that are acquired by being shot according to the stitch shooting method.
As illustrated in FIG. 9A, if an operator designates, upon completion of shooting of a second photographed image C2, misshooting or reshooting of the image C2, then, the operator inputs, to an image processing apparatus, a reason for misshooting or reshooting of the second photographed image C2. Upon completion of inputting the reason, a cross mark is displayed on the second photographed image C2. Thus, the second photographed image C2 is changed to an image C2′. Consequently, it is confirmed that the misshooting or reshooting of the image C2 is designated.
As illustrated in FIG. 9B, if a desired image is not obtained as a combined image C4 that is formed upon completion of shooting of three images C1, C2,and C3, the operator designates misshooting or reshooting of the combined image C4. If the operator designates the misshooting or reshooting of the combined image C4 similarly to the designation of the misshooting or reshooting of the image C2 illustrated in FIG. 9A, then, the operator inputs, to the image processing apparatus, a reason for misshooting or reshooting of the combined image C4. Upon completion of inputting the reason, a cross mark is displayed on the combined image C4. Thus, the combined image C4 is changed to an image C4′. Consequently, it is confirmed that the misshooting or reshooting of the combined image C4 is designated.
According to the method of the designation of misshooting or reshooting illustrated in FIGS. 9A and 9B, the designation of misshooting or reshooting is performed on a single photographed-image or combined-image. However, sometimes, such a method of the designation of misshooting or reshooting is not effective in the case of employing the stitch shooting method aimed at forming a combined image, for the following reason.
According to the stitch shooting method, even if the reshooting of the second photographed image C2 is designated as illustrated in FIG. 9A, and then performed, there is little possibility that a reshot image obtained by the reshooting of the image C2 is incorrectly combined with the first photographed image C1. This is caused by, e.g., the fact that the patient moves while the second image is reshot.
Accordingly, the designation of misshooting or reshooting of the photographed image C2 means that both of the first and second images C1 and C2 are reshot. Thus, if the misshooting or reshooting of the second photographed image C2 is designated, the misshooting or reshooting of the first photographed image C1 should also be designated.
On the other hand, if a combined image is reformed by designating the misshooting or reshooting of the combined image C4, the images C1, C2, and C3 photographed to form the combined image C4 are unnecessary. Accordingly, if the misshooting or reshooting of the combined image C4 is designated, the misshooting or reshooting of each of the photographed images C1, C2, and C3 should also be designated.
Thus, according to the conventional method of the designation of misshooting or reshooting, the designation of misshooting or reshooting of an image shot according to the stitch shooting method is not taken into consideration. For example, if the misshooting of all of the images C1 through C4 illustrated in FIG. 9B is designated, each of the designation of the misshooting and the input of the reason for the misshooting should be performed four times. Thus, the conventional method is cumbersome for operators. In addition, there is possibility that unnecessary photographed images are transferred and printed due to an operator's carelessness of the designation of misshooting.